這篇論文提出一個適用於拍攝高動範圍情境之即時色調重現演算法，並提出嵌入式系統實作技術，達到即時影像處理的目標。本演算法中，首先使用影像濾波器將輸入影像分成高頻與低頻兩個圖層，針對低頻圖層進行多次色調重現處理，以壓縮低頻圖層資訊的動態範圍，再加上高頻圖層的資訊，以達到保留高頻影像細節的目標，並有效提升暗處區域的可見度與影像細節之對比度。此外，為了減少影像處理時間以及保持畫面亮度的穩定性，視訊中的前後連續畫面分享同樣的色調曲線，使畫面不閃爍。本論文並提出多項實作本演算法於嵌入式系統的實務技術，利用系統晶片平台所內建之影像計算加速器，達成處理VGA (640 x 480 pixels) 畫面的條件下，可達每秒30個畫面(frames/s)以上的高效能表現。

This thesis presents a practical tone reproduction approach to taking videos in high dynamic range scenes and several schemes of embedded software implementation have proposed meet the real-time requirement. The algorithm first adopts a signal filter to separate high and low frequency image planes. Multiple cycles of tone mapping are then performed for the low frequency image plane to reduce its dynamic range. The algorithm boosts the visibility of image details in darker regions by attenuating the dynamic range of the low frequency plane. The image details are maintained since the high frequency plane runs only one cycle of tone mapping. The successive frames share the same set of tone curves for the reduction of the execution time as well as the consistency of brightness among frames. The proposed high dynamic range video processing system has been implemented on an embedded system. Several practical techniques that fully utilize the available hardware accelerators in a system-on-a-chip (SoC) are also proposed. The proposed system reaches the performance of processing 30 frames/s with VGA (640 x 480) resolution when the algorithm is running on the SoC platform.

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